Spacer applying and removing tool



Oct. 1, 1963 w. N. KOELLER 3,105,291

SPACER APPLYING AND REMOVING TOOL Filed July 18. 1960 INVENTOR. AKA 067267 sale United States Patent 3,105,291 S1AER APPLYING AND REMGVBJG T9015 William N. Koeller, Birmingham, Mich, assignor to Huck Manufacturing Company, Detroit, Mich, a corporation of Nlichigan Filed July 18, 1960, Ser. No. 43,452 3 Claims. (Cl. 29227) This invention relates generally to the art of securing fasteners to structural sandwiches of the type having relatively high strength skins or laminae spaced apart by a relatively weak low density core and more particularly to an improved tool for assembling and removing spacer means of helically wound form with the laminae for receiving the fastening means therethrough.

The tool of this invention is an improvement on the tool shown in application Serial No. 755,524, filed August 18, 195 8 by Milo R. Simmonds, now Patent No. 3,061,054 and is used, following drilling of a hole through the laminae and the core and removal of the portion of the core surrounding the opening, to insert a helically wound spacer between the laminae to a position in which the inner diameter of the spacer is aligned with the laminae openings. The tool is also usable to remove the spacer. The tool shown in the above application consists of an elongated shaft that is inserted through the helical spacer after the same has been partially threaded through one of the axially aligned laminae openings. The shaft, which is extended through both openings, is then swung in a generally conical path about the axis of the openings to force the spacer through the near opening to a position between the laminae and in axial alignment with the openings therein. However, one of the problems encountered with such a tool involves preventing the spacer from being threaded out the opening in the far laminae as it is being threaded into the opening in the near laminae. It is an object of this invention, therefore, to provide a tool which has means for blocking the opening in the far laminae during insertion of the spacer through the near laminae.

A further object of this invention is to provide an improved tool of the above type which has a groove in a far end portion thereof which engages the far laminae at the edge of the opening therein to define the operative position of the tool during insertion of the spacer, and a shoulder inwardly of and adjacent the groove is of a diameter to block the far opening and prevent acicdenta-l movement of the spacer therethrough.

Further objects, features and advantages of this invention will become apparent from a consideration of the following description, the appended claims and the accompanying drawing in which:

FIGURE 1 is a sectional view of a structural sandwich having a spacer assembled therein and a fastener, of lockbolt type, secured to the sandwich;

FIG. 2 is an elevau'onal view of the spacer applying and removing tool of this invention shown in a position for initially inserting a spacer in the sandwich structure;

FIG. 3 is an elevational view of the tool of this invention shown in a position for completing the assembly of the spacer with the sandwich structure, 'and illustrating a moved position of the tool in broken lines;

FIG. 4 is a transverse sectional view of the structure shown in FIG. 3 looking substantially along the line 44;

FIG. 5 is an enlarged sectional view of the structure shown in FIG. 3 looking substantially along the line 5-5; and

FIG. 6 is a fragmentary view of the tool of this invention shown in a position for removing a spacer from the sandwich structure.

With reference to the drawing, the tool of this invention, indicated generally at 10, is illustrated in FIGS. 2 and 3 as consisting of an elongated shaft 12 having a knurled handle .14 on one end thereof. At its inner end, the handle 14 is tapered and is formed with longitudinally extending serrations 16. The opposite end of the shaft 12 is formed with a head 18 which is of an enlarged diameter relative to the shaft 12 and is gent'n ally cylindrical in shape. The head 18 is vformed intermediate its ends with a peripheral groove 20 and the portion 22 of the head 18 inwardly of and adjacent the groove 20 constitutes a shoulder of predetermined diameter for a purpose to appear presently.

The tool .10 is intended for inserting a spacer 24, of helically wound form, in a sandwich structure 26 which consists of spaced skins or laminae 28 and 30, hereinafter referred to as the near and far lamina, respectively, for convenience of description. A low density reinforcing core material 32 which may be formed of a plastic material or a very thin gauge metal is positioned between the laminae 28 and 36} for strengthening the sandwich 26.

In the assembly of a fastener, such as the lockbolt 34 (FIG. 1) which consists of a pin 35 having a collar 37 swaged into locking engagement therewith, with the sandwich structure 26 to mount an angle 36 thereon, it is necessary to first assemble the spacer 24 with the sandwich structure 26 to prevent crushing of the core material 32 and deformation of the laminae 28 and 30. This is accomplished by first drilling the hole in the sandwich structure 26 so that an opening 38 is formed in the lamina 28 and a corresponding opening 40 is formed in the lamina 36 in axial alignment with the opening 38, with the core material 32 between the openings 38 and 40 being removed by the drilling operation. The core material surrounding the drilled opening is then removed, by the use of a suitable tool such as the one shown in the copending application of Harold G. Brilmyer, Serial No. 42,327 filed July 12, l960, so that the spacer 24 can be installed without obstructing the openings 38 and 40. The spacer 24 is of helical wound form, resembling a spring in appearance, and has an inner diameter at least equal to the diameter of the openings 38 and 40 so that it will not interfere with insertion of the pin 35 through the open ings 38 and 49. The spacer 24 is of a solid length in its closed condition shown in FIG. 1 substantially equal to the spacing between the laminae 28 and 30 so that loads are transferred directly to the laminae 23 and 30 from the fastener 34 without crushing the low density core material 32.

In the use of the tool 11 to assemble the spacer 24 with the sandwich structure 26, the spacer 24 is mounted on the shaft 12 so that the serrations 16 on handle 14 engage one end 42 of the spacer 24. The shaft 12 is extended through the aligned laminae openings 38 and 40 by first extending the head 18 on the shaft 12 through the openings 38 and 4%, following which the tool '10 is manipulated so that the opposite end 44 of the spacer 24' is threaded through the opening 38 in the lamina 28. Hand pressure is exerted on the handle 14 in a direction axially of the shaft 12 concurrently with rotating the handle 14 to rotate the shaft 12. This action results in transferring the rotational force of the handle 14 to the spacer 24 through the serrations 16 which engage the end 42 of the spacer 24 and several of the adjacent coils of the spacer 24.

When the spacer 24 has been started through the opening 38 so that one or more coils of the spacer 24 at the end 44 thereof have been positioned between the laminae 28 and 30, the tool 12 is withdrawn to the position illustrated in FIG. 3 in which the groove 20 in the head 18 is positioned at the opening 40 in the far lamina 30 and the lamina 3d at one side of the opening 40 extends into the groove 2%. This engagement of the head 18 with the far lamina 39 positively locates the tool in an operative position for further threading the spacer 24- into the structural sandwich 26. The tool It is then manipulated so 7 threaded through the opening 38. This action is continued until the spacer 24 is in approximately the position illustrated in FIG. 1.

Describing the above action in more detail, the handle 14 is swung in a direction opposite to the direction of rotation thereof to initially thread the spacer 24 into the opening 38. The handle 14 is swung in a frusto-conical path about the axis of the openings 33 and 4% While maintaining contact between the head 18 at the groove 20 and the side edge of the opening 4% with the shaft 12 continuously engaging a portion of the spacer outwardly of and adjacent the diametrically opposite side edge of the opening 38 so as to progressively move these portions of the spacer 24 through the opening 38. The shaft 12 rolls around the periphery of the opening 3% and the head 18 rolls around the periphery of the opening 49 and at or near the point Where the shaft 12 contacts the near lamina 28 at the opening 3-8 the spacer 24 is forced through the near opening 38 and as the shaft 12 moves around the edge of the opening it continually moves the spacer to a new entry point closer to the end 42 thereof. Due to the friction between the shaft 12 and the spacer 24 in the above operation, the spacer 24 rotates very slowly in the same direction that the tool 10 is being rotated. This action is continued until the spacer 24 is entirely between the laminae 28 and 30.

It can thus be seen that the spacer 24 is rotated about its axis in one direction until it is partially threaded through the opening 38 and then the spacer is moved in an opposite direction in a generally conical path about the axis of the opening 38. Several rotations in the latter direction are sufiicient to position the spacer 24 between the laminae 28 and 3%. The shoulder 22 on the head 13 is of a diameter such that it blocks the far opening 4% to prevent the spacer 24 from being threaded out the'opening 4% during the final movement of the spacer into the opening 38.

Thus, for different size spacers, a different tool 10 is utilized having a shoulder 22 which is of a diameter only slightly less than the diameter of the lamina opening 44}, so that it substantially covers the opening 46 to prevent travel of the spacer therethrough. As the inserting tool 12 is removed, travel of the head 18 through the openings 40 and 38 further insures centering of the spacer 24 so that the spacer is ready to have the pin or a bolt or the like inserted therethrough for attaching the member 35 to the sandwich structure 26.

To remove the spacer 24, the head 18 can be inserted in either the opening 38 or the opening 44 depending on the desired direction of removal of the spacer 24. If the spacer 24 is to be removed through the opening 38, as shown in FIG. 6, the head 18 is inserted through the opening to a position in which the end 50 of the head 18 is adjacent the lamina 28. The tool 12 is then manipulated to start the end 42 of the spacer 24 through the opening 38, following which the handle 14 is operated to swing the tool 10 in a conical path such that the end of the head 18 moves in a circular path adjacent the laminae opening 3% to progressively move the spacer 24 through the opening 3-8 as the head 18 engages portions of the spacer 24 closer and closer to the end 44 thereof.

it will be understood that the specific construction of the improved spacer applying and removing tool which is herein disclosed and described is presented for purposes of explanation and illustration and is not intended to indicate limits of the invention, the scope of which is defined by the following claims.

What is claimed is:

1. A tool for inserting a spring-like spacer between spaced laminae in a sandwich construction and in a coaxial relation with coaxial similar openings formed in said laminae, said tool comprising an elongated shaft of a preselected length to completely receive the spacer thereon and of a diameter substantially less than the diameter of said openings, a handle joined at one of its ends to one end of said shaft, an enlarged head at the opposite end of said shaft, said head having a groove intermediate the ends thereof and a shoulder inwardly of said head of a preselected diameter relative to the diameter of one of the openings to substantially block that one of the openings when said groove is positioned therein, said handle having said one thereof tapered and formed with serrations extending longitudinally thereof.

2. For use with a sandwich-like structure comprising a pair of spaced laminae having coaxial openings therethrough, a tool for inserting a spring-like spacer coaxially with the openings and in betweenthe spaced laminae comprising an elongated shaft having a handle at one end and an enlarged substantially cylindrical head having a predetermined diameter relative to the diameter of the openings at the opposite end, said shaft having a diameter substantially less-than the diameter of said enlarged head, said head having a circumferentially extending groove formed therein intermediate the ends thereof within a preselected distance of said opposite end of said shaft with said head being secured to said shaft at a point removed from said groove, and means on said handle including a roughened surface being selectively engageable with the spacer for initiating the insertion of a spacer through one of the openings.

3. For usewith a sandwich-like structure comprising a pair of spaced laminae having coaxial openings therethrough, a tool for inserting a spring-like spacer coaxially with the openings and in between the spaced laminae comprising an elongated shaft having a handle atone end and an enlarged substantially cylindrical head having a predetermined diameter relative to the diameter of the openings at the opposite end, said shaft having a diameter substantially less than the diameter of the openings, said head having a circumferentially extending groove formed therein intermediate the ends thereof Within a preselected distance of said opposite end of said shaft, and means on said handle including a roughened surface being selectively engageable with the spacer for initiating the insertion of the spacer through one of the openings.

References Cited in the file of this patent UNITED STATES PATENTS 1,328,428 Graham Jan. 20, 1920 2,094,432 Pazzano Sept. 28, 1937 2,864,273 Hentosh Dec. 16, 1958 2,875,651 Kissinger et al Mar. 3, 1959 3,061,054 Simmonds Oct. 30, 1962 

2. FOR USE WITH A SANDWICH-LIKE STRUCTURE COMPRISING A PAIR OF SPACED LAMINAE HAVING COAXIAL OPENINGS THERETHROUGH, A TOOL FOR INSERTING A SPRING-LIKE SPACER COAXIALLY WITH THE OPENINGS AND IN BETWEEN THE SPACED LAMINAE COMPRISING AN ELONGATED SHAFT HAVING A HANDLE AT ONE END AND AN ENLARGED SUBSTANTIALLY CYLINDRICAL HEAD HAVING A PREDETERMINED DIAMETER RELATIVE TO THE DIAMETER OF THE OPENINGS AT THE OPPOSITE END, SAID SHAFT HAVING A DIAMETER SUBSTANTIALLY LESS THAN THE DIAMETER OF SAID ENLARGED HEAD, SAID HEAD HAVING A CIRCUMFERENTIALLY EXTENDING GROOVE FORMED THEREIN INTERMEDIATE THE ENDS THEREOF WITHIN A PRESELECTED DISTANCE OF SAID OPPOSITE END OF SAID SHAFT WITH SAID HEAD BEING SECURED TO SAID SHAFT AT A POINT REMOVED FROM SAID GROOVE, AND MEANS ON SAID HANDLE INCLUDING A ROUGHENED SURFACE BEING SSELECTIVELY ENGAGEABLE WITH THE SPACER FOR INITIATING THE INSERTION OF SPACER THROUGH ONE OF THE OPENINGS. 